The importance of preserving immigration documents cannot be over emphasized. Providing the CIS with a required document can mean the difference between a benefit being granted or denied in many cases. In today's digital world, it is very easy to scan documents and preserve them. There is no valid excuse for failing to do so.

You should make and maintain copies of all of the following documents:

• All pages of your current passport (be sure to update this file after every trip abroad).
• All pages of all of your old passports.
• All forms I-797 (receipt notices, RFEs, approvals, etc.)
• Your current and all prior forms I-94.
• Paystubs
• Forms W-2 and 1099
• State and federal tax returns
• Employment agreements
• Training certificates
• Airline boarding passes (both outbound and inbound)

Often, the CIS will want to see some of these documents in order to establish your eligibility for a benefit. For example, airline boarding passes and passport stamps establish time spent outside the US for H1B time recapture purposes.

Pay stubbs W-2, and tax returns not only establish that you have mainained status, but also can help prove "ability to pay" for I-140 purposes.